One technique used to mask malicious software is to encrypt a file that includes the malicious software. Traditional software security measures (e.g., firewalls, spyware and malware filters, antivirus software, etc.) are often unable to identify the malicious software because of the encryption. In some cases, the encrypted file that includes the malicious software may be decrypted using a password that is given to the recipient of the file. When the recipient enters the password and decrypts the file, the malicious code often has already successfully survived pertinent security measures and is able to perform its nefarious task.